Sports Direct will step up its challenge to Decathlon's European dominance when it opens its first Spanish store in April.

The UK's largest sportswear retailer will open in the north-east city of Zaragoza, adding to overseas stores in France, Belgium, Portugal, Holland, Hungary, Slovenia and the Czech Republic.

Sports Direct – which the Newcastle United owner Mike Ashley founded from a single shop in Maidenhead in 1982 – has powered through the UK consumer downturn and took 20 stores from failed rival JJB Sports last year.

Mr Ashley, the group's deputy executive chairman, has relentlessly expanded the retailer to 398 UK stores, and has pursued a strategy of buying brands, such as Everlast, Donnay, Karrimor and Lonsdale, which he then licences to other retailers around the world.

Last month, Sports Direct said its strategy "remains to expand our international retail operations into all 17 countries that have adopted the euro currency within five years".

While there is limited overlap of both chains' store estates currently, industry experts believe that Sports Direct and France's Decathlon will battle each other for supremacy over the coming decade in Europe. Decathlon has nearly 550 shops, including 14 in the UK.